21374332310551 has 4 divisors (see below), whose sum is σ = 23317453429704. Its totient is φ = 19431211191400.

The previous prime is 21374332310549. The next prime is 21374332310579. The reversal of 21374332310551 is 15501323347312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21374332310551 - 2¹ = 21374332310549 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21374332314551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 971560559560 + ... + 971560559581.

It is an arithmetic number, because the mean of its divisors is an integer number (5829363357426).

Almost surely, 2^{21374332310551} is an apocalyptic number.

21374332310551 is a deficient number, since it is larger than the sum of its proper divisors (1943121119153).

21374332310551 is a wasteful number, since it uses less digits than its factorization.

21374332310551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1943121119152.

The product of its (nonzero) digits is 226800, while the sum is 40.

Adding to 21374332310551 its reverse (15501323347312), we get a palindrome (36875655657863).

The spelling of 21374332310551 in words is "twenty-one trillion, three hundred seventy-four billion, three hundred thirty-two million, three hundred ten thousand, five hundred fifty-one".